As a propulsion apparatus used in the space, an MPD thruster (Magneto-Plasma-Dynamic thruster) is known. FIG. 1 shows an example of the MPD thruster. The MPD thruster generates plasma by ionizing propellant (gas) with arc discharge. Lorentz force is generated by current that flows between an anode arranged on the outer circumference side of the thruster and a cathode arranged on the center side, and a magnetic field that is generated by the current (or a previously applied magnetic field). The generated plasma is accelerated with Lorentz force.
As techniques related to the propulsion apparatus used in the space, JP H05-45797B1 (Japanese Patent No. 1,836,674) discloses an electric propulsion machine that obtains thrust force by emitting the plasma generated with the arc discharge from a nozzle. Japanese Patent No. 4,925,132 discloses an ion engine that selectively accelerates charged particles formed through the discharge by using a screen electrode and an acceleration electrode.